I planted a package of 6 lilies. 4 bloomed and 2 did not. However, the 2 that did not bloom appear to have bulbils growing at the top (not along the stem). I have never had this happen. Have any of you?

It's not all that unusual... some lilies will do that if they are stressed. I collected bulbils from the top of an unidentified lily a couple of years ago and they bloomed this year. Turned out to be Asiatic lily Belo Horizonte. I have also had these top bulbils form on an Oriental lily and a trumpet lily.